This invention is related to antennas and to an antenna feed array for broadband operation at microwave-frequencies.
Reflector antennas are widely used, particularly for microwave frequency radio waves. Reflector antennas include a reflector and a feed. The reflector commonly has a parabolic shape. The feed couples radio waves reflected by the reflector to and from electronics. The radio waves are transmitted and received from a part of the feed located at or near the focus of the reflector.
Radar systems commonly use reflector antennas. The monopulse radar technique uses sum and difference signals corresponding to offset beams, that is, beams that originate from the same point but that are slightly divergent. Processing the sum and difference signals provides accurate direction detection. Accordingly, controlling the direction and pattern of the beams is important to the performance of a radar system. Radar systems may use different frequencies, for example, to differentiate materials that differently reflect or absorb different frequencies. Thus, a broadband antenna that operates over a wide frequency band is desirable. Controlling the beams patterns is increasingly difficult as the operating bandwidth increases.